The free path in a high velocity random flight process associated to a Lorentz gas in an external field

We investigate the asymptotic behavior of the free path of a variable density random flight model in an external field as the initial velocity of the particle goes to infinity. The random flight models we study arise naturally as the Boltzmann-Grad limit of a random Lorentz gas in the presence of an external field. By analyzing the time duration of the free path, we obtain exact forms for the asymptotic mean and variance of the free path in terms of the external field and the density of scatterers. As a consequence, we obtain a diffusion approximation for the joint process of the particle observed at reflection times and the amount of time spent in free flight.Comment: 30 page

Asymptotic harvesting of populations in random environments

We consider the harvesting of a population in a stochastic environment whose dynamics in the absence of harvesting is described by a one dimensional diffusion. Using ergodic optimal control, we find the optimal harvesting strategy which maximizes the asymptotic yield of harvested individuals. To our knowledge, ergodic optimal control has not been used before to study harvesting strategies. However, it is a natural framework because the optimal harvesting strategy will never be such that the population is harvested to extinction-instead the harvested population converges to a unique invariant probability measure. When the yield function is the identity, we show that the optimal strategy has a bang-bang property: there exists a threshold [Formula: see text] such that whenever the population is under the threshold the harvesting rate must be zero, whereas when the population is above the threshold the harvesting rate must be at the upper limit. We provide upper and lower bounds on the maximal asymptotic yield, and explore via numerical simulations how the harvesting threshold and the maximal asymptotic yield change with the growth rate, maximal harvesting rate, or the competition rate. We also show that, if the yield function is [Formula: see text] and strictly concave, then the optimal harvesting strategy is continuous, whereas when the yield function is convex the optimal strategy is of bang-bang type. This shows that one cannot always expect bang-bang type optimal controls

MIR-423-3P USED AS REFERENCE GENE FOR MIRNA 146 A IN CELL LINES HEP-G2

Objective: We explored the stable reference genes for miRNA 146 A by RT-PCR in the cell lines Hep-G2 that were treated chlorogenic acid. We must do a series of tests in order to get a reference genes. Based on the literature there are 7 candidates recommended reference genes; mir-423-3p, 423-5p, 191, 103, 21, 16, and let-7a. We conducted using four candidates reference gene; mir-423-3p, 103, 16, and 21. Methods: In vitro study was performed in Hep-G2 cells. The samples were divided into control group and experiment group treated with 727μM chlorogenic acid. Samples were analyzed at 0, 2, 8, 18, and 24 hours after being treated with chlorogenic acid. Total RNA was isolated from Hep-G2 with RNA extraction kit (miRCURYTM RNA Isolation Kit-Cell and plant Exiqon, Code Number 300110) and reverse transcribed to cDNA with Primerscript RT Reagent Kit (miRCURY LNATM Universal RT microRNA PCR, Polyadenylation and cDNA synthesis kit Exiqon, Code Number 203300). The primers for miRNA 146 A were Code Number 204688 from Exiqon (forward and reverse), and quantitative real time reverse transcription polymerase chain reaction was performed using SYBR Master Mix with Code Number 203450 (Exicon). MiRNA profiling was performed in four pairs of mir, consist of; mir-423-3p, 103, 21, and mir-16. By using the mean expression value of all expressed mir, we identified the most stable candidate reference genes for subsequent validation with normfinder software. Results: Data from RT-PCR were analyzed using Normfinder software. We found out that mir expression with good stablity is mir-103 and the best combination from two genes are mir-103 and mir-423-3p. Finally mir-423-3p is found more stable than mir-16, 21, and 103. Conclusion: We conclude the stable reference genes for miRNA 146 A treated with chlorogenic acid is mir-423-3p

Investigation of altering single-nucleotide polymorphism density on the power to detect trait loci and frequency of false positive in nonparametric linkage analyses of qualitative traits

Genome-wide linkage analysis using microsatellite markers has been successful in the identification of numerous Mendelian and complex disease loci. The recent availability of high-density single-nucleotide polymorphism (SNP) maps provides a potentially more powerful option. Using the simulated and Collaborative Study on the Genetics of Alcoholism (COGA) datasets from the Genetics Analysis Workshop 14 (GAW14), we examined how altering the density of SNP marker sets impacted the overall information content, the power to detect trait loci, and the number of false positive results. For the simulated data we used SNP maps with density of 0.3 cM, 1 cM, 2 cM, and 3 cM. For the COGA data we combined the marker sets from Illumina and Affymetrix to create a map with average density of 0.25 cM and then, using a sub-sample of these markers, created maps with density of 0.3 cM, 0.6 cM, 1 cM, 2 cM, and 3 cM. For each marker set, multipoint linkage analysis using MERLIN was performed for both dominant and recessive traits derived from marker loci. Our results showed that information content increased with increased map density. For the homogeneous, completely penetrant traits we created, there was only a modest difference in ability to detect trait loci. Additionally, as map density increased there was only a slight increase in the number of false positive results when there was linkage disequilibrium (LD) between markers. The presence of LD between markers may have led to an increased number of false positive regions but no clear relationship between regions of high LD and locations of false positive linkage signals was observed

Fatigue, reduced sleep quality and restless legs syndrome in Charcot-Marie-Tooth disease: a web-based survey

To investigate the prevalence of fatigue, daytime sleepiness, reduced sleep quality, and restless legs syndrome (RLS) in a large cohort of patients with Charcot-Marie-Tooth disease (CMT) and their impact on health-related quality of life (HRQoL). Participants of a web-based survey answered the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the Multidimensional Fatigue Inventory, and, if the diagnostic criteria of RLS were met, the International RLS Severity Scale. Diagnosis of RLS was affirmed in screen-positive patients by means of a standardized telephone interview. HRQoL was assessed by using the SF-36 questionnaire. Age- and sex-matched control subjects were recruited from waiting relatives of surgical outpatients. 227 adult self-reported CMT patients answered the above questionnaires, 42.9% were male, and 57.1% were female. Age ranged from 18 to 78 years. Compared to controls (n = 234), CMT patients reported significantly higher fatigue, a higher extent and prevalence of daytime sleepiness and worse sleep quality. Prevalence of RLS was 18.1% in CMT patients and 5.6% in controls (p = 0.001). RLS severity was correlated with worse sleep quality and reduced HRQoL. Women with CMT were affected more often and more severely by RLS than male patients. With regard to fatigue, sleep quality, daytime sleepiness, RLS prevalence, RLS severity, and HRQoL, we did not find significant differences between genetically distinct subtypes of CMT. HRQoL is reduced in CMT patients which may be due to fatigue, sleep-related symptoms, and RLS in particular. Since causative treatment for CMT is not available, sleep-related symptoms should be recognized and treated in order to improve quality of life

Metabolic Characterization of a Sirt5 deficient mouse model

Sirt5, localized in the mitochondria, is a member of sirtuin family of NAD(+)-dependent deacetylases. Sirt5 was shown to deacetylate and activate carbamoyl phosphate synthase 1. Most recently, Sirt5 was reported to be the predominant protein desuccinylase and demalonylase in the mitochondria because the ablation of Sirt5 enhanced the global succinylation and malonylation of mitochondrial proteins, including many metabolic enzymes. In order to determine the physiological role of Sirt5 in metabolic homeostasis, we generated a germline Sirt5 deficient (Sirt5(-/-)) mouse model and performed a thorough metabolic characterization of this mouse line. Although a global protein hypersuccinylation and elevated serum ammonia during fasting were observed in our Sirt5(-/-) mouse model, Sirt5 deficiency did not lead to any overt metabolic abnormalities under either chow or high fat diet conditions. These observations suggest that Sirt5 is likely to be dispensable for the metabolic homeostasis under the basal conditions

The Metrological Traceability, Performance and Precision of European Radon Calibration Facilities

An interlaboratory comparison for European radon calibration facilities was conducted to evaluate the establishment of a harmonized quality level for the activity concentration of radon in air and to demonstrate the performance of the facilities when calibrating measurement instruments for radon. Fifteen calibration facilities from 13 different European countries participated. They represented different levels in the metrological hierarchy: national metrology institutes and designated institutes, national authorities for radiation protection and participants from universities. The interlaboratory comparison was conducted by the German Federal Office for Radiation Protection (BfS) and took place from 2018 to 2020. Participants were requested to measure radon in atmospheres of their own facilities according to their own procedures and requirements for metrological traceability. A measurement device with suitable properties was used to determine the comparison values. The results of the comparison showed that the radon activity concentrations that were determined by European calibration facilities complying with metrological traceability requirements were consistent with each other and had common mean values. The deviations from these values were normally distributed. The range of variation of the common mean value was a measure of the degree of agreement between the participants. For exposures above 1000 Bq/m3, the variation was about 4% for a level of confidence of approximately 95% (k=2). For lower exposure levels, the variation increased to about 6%

Genetic Analysis Workshop 14: microsatellite and single-nucleotide polymorphism marker loci for genome-wide scans.

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Algorithms for the diagnosis and treatment of restless legs syndrome in primary care

<p>Abstract</p> <p>Background</p> <p>Restless legs syndrome (RLS) is a neurological disorder with a lifetime prevalence of 3-10%. in European studies. However, the diagnosis of RLS in primary care remains low and mistreatment is common.</p> <p>Methods</p> <p>The current article reports on the considerations of RLS diagnosis and management that were made during a European Restless Legs Syndrome Study Group (EURLSSG)-sponsored task force consisting of experts and primary care practioners. The task force sought to develop a better understanding of barriers to diagnosis in primary care practice and overcome these barriers with diagnostic and treatment algorithms.</p> <p>Results</p> <p>The barriers to diagnosis identified by the task force include the presentation of symptoms, the language used to describe them, the actual term "restless legs syndrome" and difficulties in the differential diagnosis of RLS.</p> <p>Conclusion</p> <p>The EURLSSG task force reached a consensus and agreed on the diagnostic and treatment algorithms published here.</p